[Isolation of a bacterial strain capable of bezafibrate-degrading and biodegradation characteristics].

OBJECTIVE: Bezafibrate is one of the most frequently detected pharmaceuticals at relatively high concentration in surface water and even in drinking water. Biodegradation is an important way to solve the problem. This study aimed to isolate, identify and characterize a bezafibrate-degrading bacterium.

METHODS: Strain B31 capable of degrading bezafibrate by cometabolism was isolated from activated sludge of sewage treatment plant in Shanghai, China, and identified based on its morphology, physiology and phylogenetic analysis of 16S rRNA sequence. To evaluate the ability of degradation, the concentration of bezafibrate was detected by high performance liquid chromatography.

RESULTS: Strain B31 was identified to be closely related to Pseudomonas putida. The optimum condition of degrading bezafibrate was at 30 degrees C, pH 7. After 5 days, Strain B31 could degrade 30 mg/L bezafibrate by 48% in liquid mineral salt medium with 1% methanol as primary substrate. And the rate of degradation could enhance to 61%, 72.6%, 76.67%, when 5 g/L glucose, peptone and yeast extract as primary substrate, respectively.

CONCLUSION: The strain has the potential for bezafibrate biodegradation.